High intensity focused ultrasound (HIFU) is increasingly used for treating internal body tissues of patients in a minimally invasive manner. In order to accurately treat relatively deep tissues such as the uterus, it is generally desirable to increase the size of a HIFU transducer used to produce the HIFU signals in order to achieve desired focal characteristics. On the other hand, it is also important to have a clear acoustic window for delivery of the HIFU signals to the target tissues. For example, in order to maintain a clear acoustic window when treating tissues in the uterus, it is desirable that the applicator fit within an area between the patient's pubic bone and the umbilicus.
Given these competing concerns, there is a need for technology that allows for increasing the size of the HIFU transducer in a HIFU applicator system while managing the size of the footprint of the HIFU applicator.